Girls are 5-6 yrs old and one has suddenly stopped getting up on her roost. She seems to not be able to walk well and is not steady on her feet. She will drink and is also interested in eating. Back feathers are fluffed. I checked for a stuck egg and it does not feel that is the problem. I brought her inside today and she appeared to have healthy poops. Any suggestions or things I could look for. Thank you so much.